TY - GEN A1 - Brinkert, Katharina A1 - Richter, Matthias A1 - Akay, Ömer A1 - Giersig, Michael A1 - Fountaine, Katherine T. A1 - Lewerenz, Hans-Joachim T1 - Advancing semiconductor-electrocatalyst systems: application of surface transformation films and nanosphere lithography T2 - Faraday Discussions N2 - Photoelectrochemical (PEC) cells offer the possibility of carbon-neutral solar fuel production through artificial photosynthesis. The pursued design involves technologically advanced III–V semiconductor absorbers coupled via an interfacial film to an electrocatalyst layer. These systems have been prepared by in situ surface transformations in electrochemical environments. High activity nanostructured electrocatalysts are required for an efficiently operating cell, optimized in their optical and electrical properties. We demonstrate that shadow nanosphere lithography (SNL) is an auspicious tool to systematically create three-dimensional electrocatalyst nanostructures on the semiconductor photoelectrode through controlling their morphology and optical properties. First results are demonstrated by means of the photoelectrochemical production of hydrogen on p-type InP photocathodes where hitherto applied photoelectrodeposition and SNL-deposited Rh electrocatalysts are compared based on their J–V and spectroscopic behavior. We show that smaller polystyrene particle masks achieve higher defect nanostructures of rhodium on the photoelectrode which leads to a higher catalytic activity and larger short circuit currents. Structural analyses including HRSEM and the analysis of the photoelectrode surface composition by using photoelectron spectroscopy support and complement the photoelectrochemical observations. The optical performance is further compared to theoretical models of the nanostructured photoelectrodes on light scattering and propagation. KW - shadow nanosphere lithography (SNL) KW - electrocatalyst nanostructures KW - Rh electrocatalysts KW - InP photocathodes Y1 - 2018 U6 - https://doi.org/10.1039/C8FD00003D SN - 1359-6640 SN - 1364-5498 VL - 208 SP - 523 EP - 535 ER -